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<div class="section">
<div class="titlepage"><div><div><h5 class="title">
<a name="fusion.functional.invocation.functions.invoke"></a><a class="link" href="invoke.html" title="invoke">invoke</a>
</h5></div></div></div>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h0"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.description"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.description">Description</a>
          </h6>
<p>
            Calls a <a class="link" href="../../concepts/def_callable.html" title="Deferred Callable Object">Deferred
            Callable Object</a> with the arguments from a <a class="link" href="../../../sequence.html" title="Sequence">Sequence</a>.
          </p>
<p>
            The first template parameter can be specialized explicitly to avoid copying
            and/or to control the const qualification of a function object.
          </p>
<p>
            If the target function is a pointer to a class members, the corresponding
            object can be specified as a reference, pointer, or smart pointer. In
            case of the latter, a freestanding <code class="literal">get_pointer</code> function
            must be defined (Boost provides this function for <code class="literal">std::auto_ptr</code>
            and <a href="http://www.boost.org/libs/smart_ptr#shared_ptr" target="_top"><code class="computeroutput"><span class="identifier">boost</span><span class="special">::</span><span class="identifier">shared_ptr</span></code></a>).
          </p>
<p>
            Constructors can be called applying <a href="http://www.boost.org/libs/functional/factory" target="_top">Boost.Functional/Factory
            Library</a>.
          </p>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h1"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.synopsis"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.synopsis">Synopsis</a>
          </h6>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <span class="identifier">Function</span><span class="special">,</span>
    <span class="keyword">class</span> <span class="identifier">Sequence</span>
    <span class="special">&gt;</span>
<span class="keyword">typename</span> <a class="link" href="../metafunctions/invoke.html" title="invoke"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">invoke</span></code></a><span class="special">&lt;</span><span class="identifier">Function</span><span class="special">,</span> <span class="identifier">Sequence</span><span class="special">&gt;::</span><span class="identifier">type</span>
<span class="identifier">invoke</span><span class="special">(</span><span class="identifier">Function</span> <span class="identifier">f</span><span class="special">,</span> <span class="identifier">Sequence</span> <span class="special">&amp;</span> <span class="identifier">s</span><span class="special">);</span>

<span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <span class="identifier">Function</span><span class="special">,</span>
    <span class="keyword">class</span> <span class="identifier">Sequence</span>
    <span class="special">&gt;</span>
<span class="keyword">typename</span> <a class="link" href="../metafunctions/invoke.html" title="invoke"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">invoke</span></code></a><span class="special">&lt;</span><span class="identifier">Function</span><span class="special">,</span> <span class="identifier">Sequence</span> <span class="keyword">const</span><span class="special">&gt;::</span><span class="identifier">type</span>
<span class="identifier">invoke</span><span class="special">(</span><span class="identifier">Function</span> <span class="identifier">f</span><span class="special">,</span> <span class="identifier">Sequence</span> <span class="keyword">const</span> <span class="special">&amp;</span> <span class="identifier">s</span><span class="special">);</span>
</pre>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h2"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.parameters"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.parameters">Parameters</a>
          </h6>
<div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Parameter
                    </p>
                  </th>
<th>
                    <p>
                      Requirement
                    </p>
                  </th>
<th>
                    <p>
                      Description
                    </p>
                  </th>
</tr></thead>
<tbody>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">f</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      A <a class="link" href="../../concepts/def_callable.html" title="Deferred Callable Object">Deferred
                      Callable Object</a>
                    </p>
                  </td>
<td>
                    <p>
                      The function to call.
                    </p>
                  </td>
</tr>
<tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">s</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      A <a class="link" href="../../../sequence/concepts/forward_sequence.html" title="Forward Sequence">Forward
                      Sequence</a>
                    </p>
                  </td>
<td>
                    <p>
                      The arguments.
                    </p>
                  </td>
</tr>
</tbody>
</table></div>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h3"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.expression_semantics"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.expression_semantics">Expression
            Semantics</a>
          </h6>
<pre class="programlisting"><span class="identifier">invoke</span><span class="special">(</span><span class="identifier">f</span><span class="special">,</span><span class="identifier">s</span><span class="special">);</span>
</pre>
<p>
            <span class="bold"><strong>Return type</strong></span>: Return type of <code class="computeroutput"><span class="identifier">f</span></code> when invoked with the elements in
            <code class="computeroutput"><span class="identifier">s</span></code> as its arguments.
          </p>
<p>
            <span class="bold"><strong>Semantics</strong></span>: Invokes <code class="computeroutput"><span class="identifier">f</span></code>
            with the elements in <code class="computeroutput"><span class="identifier">s</span></code>
            as arguments and returns the result of the call expression.
          </p>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h4"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.header"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.header">Header</a>
          </h6>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">functional</span><span class="special">/</span><span class="identifier">invocation</span><span class="special">/</span><span class="identifier">invoke</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h5"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.example"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.example">Example</a>
          </h6>
<pre class="programlisting"><a href="http://en.cppreference.com/w/cpp/utility/functional/plus" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">plus</span></code></a><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">add</span><span class="special">;</span>
<span class="identifier">assert</span><span class="special">(</span><span class="identifier">invoke</span><span class="special">(</span><span class="identifier">add</span><span class="special">,</span><a class="link" href="../../../container/generation/functions/make_vector.html" title="make_vector"><code class="computeroutput"><span class="identifier">make_vector</span></code></a><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">1</span><span class="special">))</span> <span class="special">==</span> <span class="number">2</span><span class="special">);</span>
</pre>
<h6>
<a name="fusion.functional.invocation.functions.invoke.h6"></a>
            <span class="phrase"><a name="fusion.functional.invocation.functions.invoke.see_also"></a></span><a class="link" href="invoke.html#fusion.functional.invocation.functions.invoke.see_also">See
            also</a>
          </h6>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
                <a class="link" href="invoke_proc.html" title="invoke_procedure"><code class="computeroutput"><span class="identifier">invoke_procedure</span></code></a>
              </li>
<li class="listitem">
                <a class="link" href="invoke_fobj.html" title="invoke_function_object"><code class="computeroutput"><span class="identifier">invoke_function_object</span></code></a>
              </li>
<li class="listitem">
                <a class="link" href="../metafunctions/invoke.html" title="invoke"><code class="computeroutput"><span class="identifier">result_of</span><span class="special">::</span><span class="identifier">invoke</span></code></a>
              </li>
<li class="listitem">
                <a class="link" href="../../adapters/fused.html" title="fused"><code class="computeroutput"><span class="identifier">fused</span></code></a>
              </li>
<li class="listitem">
                <a class="link" href="../../generation/functions/mk_fused.html" title="make_fused"><code class="computeroutput"><span class="identifier">make_fused</span></code></a>
              </li>
</ul></div>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2006, 2011, 2012 Joel de Guzman,
      Dan Marsden, Tobias Schwinger<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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